This invention relates to improvements in building board hoists, particularly with regard to handling of sheets of material such as gypsum, wood panelling and the like.
In the building industry building board made of gypsum and various materials is widely used. Sometimes referred to as sheet rock, it comes in standard width and length sizes of 4 ft. by 12 ft., the thickness varying from 1/2 inch to 1 inch. The thicker sheets having greater structural integrity and strength are used on larger structures. The weight of sheet rock is a serious problem in handling it, a 4 ft by 12 ft sheet 1/2 inch thick, for example, weighing 112 pounds. In order to enable men to apply sheet rock to high ceilings scaffolding must be erected and the building board must be lifted to the structure to which it is to be attached. The handling of sheet rock by the workmen often results in injuries. Neck and back injuries caused by overhead handling of building board materials are prevalent and a costly factor in medical and insurance plans for workmen.
Recognizing such problems the prior art sought to facilitate the overhead handling of building boards by inventing hoists for that purpose. However useful, the prior art hoists are generally complex, expensive machines. Some of them have a tendency to unduly jostle the board and cause expensive breakage. Others do not approach the working surface as closely as desired for ease of handling.
For these and other reasons, a simply constructed, sturdy and inexpensive hoist for placing building board in working proximity to the structure to which it is to be affixed is desired.